Well, I don't think Sam having sex with Ruby is horrible. Not sure it's the best decision in the world, but I certainly don't blame him. He was vulnerable and in need of connection. Plus, the guy hasn't had sex since season 2! I don't think he's in love with her though, which kind of makes it sad if she does have feelings for him. It's true that he's known Ruby a long time, but how much does he really know about her? He knows she's a ruthless, manipulative demon who's saved his life.
But I don't think Dean having sex with a fallen angel was just about getting laid. I think they had a genuine connection and having sex that night was more about mutual comfort than "bow chica bow bow".
Plus, if you just compare the sex scenes- Dean/Anna is more tender; they actually make eye contact, whereas Sam/Ruby just go at it like animals. That probably has a lot to do with people's impressions of the two moments.
But I don't think Dean having sex with a fallen angel was just about getting laid. I think they had a genuine connection and having sex that night was more about mutual comfort than "bow chica bow bow".
Plus, if you just compare the sex scenes- Dean/Anna is more tender; they actually make eye contact, whereas Sam/Ruby just go at it like animals. That probably has a lot to do with people's impressions of the two moments.